Molecular structure of the 1:1 inclusion complex of monensin A sodium salt with acetonitrile

✍ Scribed by Adam Huczyński; Małgorzata Ratajczak-Sitarz; Andrzej Katrusiak; Bogumil Brzezinski

• Book ID: 104058619
• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 355 KB
• Volume: 832
• Category: Article
• ISSN: 0022-2860
• DOI: 10.1016/j.molstruc.2006.07.043

✦ Synopsis

Crystal structure of the inclusion crystal of monensin A sodium salt with acetonitrile, Na(C 36 H 61 O 11 ) CH 3 CN, has been studied by X-ray diffraction, FT-IR spectroscopy, and PM5 semiempirical methods. The space group of the crystal is P2 1 2 1 2 1 with a = 12.8116(5), b = 16.5851(6), c = 18.6807( 6) and Z = 4. Within the inclusion complex the Na + cation is coordinated by six O atoms of monensin A molecule in a distorted octahedron geometry. The Na-O bond lengths are between 2.3276(13) and 2.6033(14) A ˚. The oxygen atoms of the carboxylate group are involved in two intramolecular hydrogen bonds of different strength: O(11)-HÁ Á ÁO(1) of 2.554(2) A ˚and O(10)-HÁ Á ÁO(2) of 2.683(2) A ˚. These two hydrogen bonds bind two ends of the monensin molecule, which in this way forms a pseudo cyclic structure wrapped around the Na + cation. The IR spectrum of the crystal confirms the results obtained by the X-ray study and provides spectroscopic evidence for the formation of the inclusion complex. The calculated structure of the monensin A sodium salt and the structural parameters are comparable with those determined from the X-ray data.